Silent electric switch



Aug. 3 ,1926. 1,594,676

M. M. LARAsEN SILENT ELECTRIC SWITCH Filed Jan. 6. 1925 2 Sheets-Sheet 1 Aug. 3 1926.

M. M. LARSEN SILENT ELECTRIC SWITCH Filed Jan. 6. -1925 2 `Sheetssv-Sheei: 2

- LZ/Je W www Parenteel Aug. 3, 192e;

UNITED' STATES .PATENT F Fics..

EADS M. LARSEN, 0F COLTON, CALIFORNIA.

SILENT ELECTRIC SWITCE.

Application led January 6, 1925. Serial No. B11.

provide an electric switch which will be l 10 silent in its operation` so that the switch will not produce a click when being turned off or on.

With the foregoing and other objects in4 view which will be made manifest in the 35 following detailed description and pointed out in the appended claims, reference is had to the accompanying drawings for an illustrative embodiment of the invention, wherein:

Figure 1 is a front elevation of one form of the improved switch;

Fig. 2 is a section taken substantially on the line 2-2 of Fig. 1, showing the switch in open position;

Fig. 3 is a view similar to Fig. 2, showing the switch in closed position;

Fig. 4 is a view taken substantially on the line 4-4 of Fig. 2;

Fig. 5 is a view taken substantially on the line 5-5 of Fig. 3; K

Fig. 6 is a front elevation of a modified form of the invention;

j Fig. 7 is a horizontal sectionl taken through the switch shown in Fig. 6, and may be considered as being taken on line 7-7 ofFig. 8; and

Fig. 8 is a view of the modified form of switch with the cover or face plate removed.

Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout.I they switch shown in Figs. 1 to 5 inclusive consists of a casing, generally designated at 10. This .casing ispreferably formed of a stri of sheet metal bent to provide a back wal 11 and side walls 12 and 13. Suitable blocks of insulating material 14 and 15 are Vsecured within the casing parallel `to the side walls 12 and 13. Upon the to side of the casing 10 there is mounted a b ock of insulating material 16, and upon the lower side of the casing a plate 17 is secured. A bracket 18 is secured upon the block ofinsulatin material 16 and a, spindle 19 has one end journaled in the bracket 18 and its opposite end. journaled inthe plate 17. Upon the spindle 19 there/is mounted a cam 2,0 preferably formed ohard rubber or equivalent material, although the body of the cam may be formed of metal, if so desired; and in- .serts or cushions 21 are secured within the bodyof the cam 20 and project from the faces thereof for a purpose hereinafter to be described.

A U-shaped resilient member 22' is secured by means of a nut and bolt 23 to the block of insulating material 15. Legs 24 and 25 extend across the casing 10 and are coil spring 26 is secured to the legs 24 and 25 and servesv to urge the legs towards each other, as shown in Fig. 2. Upon the-ends of the legs 24 and 25, there are mounted coil springs 27 and 28. A contact in the form of a U-shaped bracket 29 is secured to the block of insulating material 16 by screws 30. Arms 31 and 32 of the U-shaped bracket 29 are disposed above and below the legs 24 and 25 of the U-shaped resilient member 22. A clip or binding ost 33 is secured about the bolt 23 so as to e `electrically connected to the resilient member 22, and an electrical conductor or wire 34 may be secured to this clip. A second electrical conductor 35 is secured to the U-shaped contact 29 as by screws 36. A lever 37 is mounted centrally upon the spindle 19 andhas oppositely extending arms. Push buttons 38 and 39 provided with pins 40 and 41 respectively are pivotally connected l:to the arms upon the lever 37. Upon the top of the casing 10 there; is secured a plate 42, upon which is mounted a face plate 43. Aper# tures 44 are formed in the face plate 743 which register with apertures 45 formed'in .the `plate 42. The push buttons 38 and 39 are slidable in the apertures 44 and 45.

The operation of this form of switch is as Vco disposed above and below the cam 20. A

follows: When it is desired to close the v switch, the push button 38 is pushed downwardly so as to assume the position shown in Fig. 3. This movement of the push but- 25 of the resilient member 22 to separate,

and causes the\coil springs 27 and 28 to engage the armsy 32 and 31 of'the U-shaped contact respectively. In this manner an electrical connection 1s established between the conductor 34and the conductor 35, current passing from the conductor 34, through the clip 33, through the resilient member 22,

through the co11 springs 28 and 27, into the The springs 27 and 28 upon engaging with.

l the arms 32 and 31 of the Contact 29 produce button or' handle 58 is rotated, rotating the.

no noise and efficiently establish the electrical connection between the legs 24 and I 25 and the' contact 29.

When it is desired to open the switch, the push button. 39 is pressed downwardly so as to rotate the cam 20 in the opposite direction and to lift the push button 38. The resiliency of the member 22 tends to draw the legs 24 and 25 together and the spring 26 assists the resilient member 22 in this respect. The springs 27 and 28 ydisengage from the arms 31 and 32 of the contact 29, breaking the electrical connection between -the wire4 34 and the wire 35. As the cushions 21 are disposed upon all four sides ofthe cam 20, the rotation of the cam against the legs 24 and 25, when openingv the switch, will not produce any audible sound.

The modified form of the invention is similar in construction to the form shown in Figs. 1 to 5. This form of the invention consists of a casing` 50 in which there are mounted insulating blocks 51 and 52 together with a back insulatin block 53. A spindle 54 is rotatable ina racket 55 secured to the block of insulating material 53 and in a plate 56 upon which is mounteda face plate 57. The spindle 54 carries' a turn-button or handle 58 and-'alsoa cam 59 similar in construction to the cam 20. A resilient member 60 is similar tothe resilientmember 22 and carries coil springs 61 .and 62, which engage upon a U-shaped contact 63 having arms 64 and 65 similar to the' arms 31 and 32. A coil spring 66 draws the legs of the resilient member 60 towards each other, urging them to engage cushions 67 mounted upon the cam 59. Electrical conductors 68 and 69 are connected to the resilient member 60 and the contact 63, as before.

In the opera-tion of this device, the turnspindle 54 and the cam'59 so as to lseparate the legs of the resilient member 60 or to a1- low them to be drawn together by the spring 66, depending upond the position of the cam 59 when rotated.

From the above it is seen that an im proved electrical switch is provided, consisting essentially of' a U-shaped resilient member having coil springs mounted upon its legs which engage upon the arms of a U-shaped contact or bracket, that a cam is rotatable between the legs of the resilient member, which` cam is provided with cushions, and that means is provided for rotating the cam between the legs of the resilient member.

It will be understood that various changes may be made in the detail of construction without departing from the spirit or. scope of the invention as defined by the appended claims.

I claim:

1. An electric switch comprising 'a U- shaped resilient member, a U-,shaped bracket having its arms disposed outside of the legs of said resilient member, said bracket forming a contact orsaid resilient member, a cam rotatable between the legs of said resilient member, means for connecting electrical conductors to said contact and to said resilient member, and means for rotating said cam so 'as to spread the legs of s'aid resilient mem ber and establish an electrical connection between said resilient member and said contact, said cam being provided with cushion devices adapted to bear upon the legs of said resilient member as and for the purpose described.

2. Anelxectric switch comprising a resil-- ient member, a contact engageable by said resilient member, a rotatable cam disposed adjacent said member, and means for rotating said cam so asto cause it to engage, sald resilient member and produce an electrical connection between it and said contact, said cam beingb provided with a cushion engageable upon said resilient member as and for the purpose described.-

3. An electric switch comprising a resilient member, a contactengageable by said resilient member, a rotatable cam disposed adjacent said member, and means for rotating said cam so as t0 cause it to engage said resilient member and produce an electrical connection therebetween, said cam being provided with cushions engageable upon said member, and said resilient member being provided with a coil spring adapted to contact with said contact.

In testimony whereof I have signed my name to this specification.

'MADS M. LARsEN. 

